The present invention relates to containers for liquids, and more particularly, a travel mug, which reduces the rate of liquid temperature change, prevents the liquid from spilling when jolted, and allows a person to drink from an otherwise closed container.
Containers for liquids having the foregoing properties exist. However, these containers, such as insulated bottles with screw-on covers, typically have no means for unencumbered access to drinking the liquid contained therein. Other such containers may have means for opening the container to drink from it and closing the container to prevent spillage while not being so used, but are generally cumbersome and not convenient to use, especially in a moving vehicle. The jar disclosed in U.S. Pat. No. 634,742 is typical and teaches a lid which through rotation seals the jar but which requires a special tool for removal of the lid.
Still other containers have addressed the foregoing concerns by using container lids that allow ready access for drinking purposes and reduce the liquid's rate of temperature change, but such lids also allow the liquid to splash out of the container when this is not desired. Typical prior art containers are disclosed in U.S. Pat. Nos. 4,582,218; 5,018,636; and 5,102,000. The narrow band of lid sealing area such as is shown in U.S. Pat. No. 5,018,636, for example, contributes to such splashing.
Some lids have a well that retains liquid that has splashed to the top. These wells are typically divided by a vertical wall which acts as a handle for turning the lid. However, when liquid resides in the well and the drinker tips the container upward to drink, the liquid can spill unpredictably over the handle. One such lid is shown in U.S. Pat. No. 4,582,218.
Yet other lids, such as snap-on type lids, can squirt a stream of liquid on the drinker when the container is filled too full and the lid is then snapped in place on the container.
The cup disclosed in U.S. Pat. No. 2,858,041 has an interrupted recessed annular baffle ring of triangular shape to deter splashing, but the top of the container is otherwise open so that it has negligible ability to reduce the liquid's rate of temperature change.
The lids of the cups disclosed in U.S. Pat. Nos. 5,102,000 and 5,018,636 have only one opening for drinking purposes. Accordingly, while they may be utilized for either right or left handed users, a separate vent to atmosphere is not provided. The lack of such a vent adversely affects the flow of fluid out of the gap because ambient air cannot be readily introduced to replace withdrawn fluid. The lid of the combination shown in U. S. Pat. No. 4,582,218 does have diametrically opposed gaps, but requires an expensively configured cup of unusual design.
For the foregoing reasons, there is a need for a beverage container that reduces temperature changes of the liquid therein, provides improved control of the liquid while in use for drinking and while being jolted, and yet allows a user to readily drink the liquid contained therein.